Restoring Apple Music library

Hello,

I have been a loyal Apple Music user for over 10 years. Recently, I logged into my previous Apple ID, which I had stopped using due to migrating to another country and creating a new account.

To my surprise, I discovered that almost my entire Apple Music library is missing. The only content that remains is one Ed Sheeran album and my “Favorited Songs” playlist.

Could you help me understand why this happened and assist me in restoring my Apple Music library, if possible? I would greatly appreciate your support.

Thank you in advance for your assistance.